This invention relates to a transceiver system for visible images, the visible images being produced by the selective application of electrical potentials to an imaging material. A material in which visible images may be formed by chemically-produced color changes as a result of the selective use of electrical potentials, is hereinafter called an electrochromic material. With many electrochromic materials, the images are reversible, that is, they can be erased by applying a reverse potential to the imaging material.
Various imaging systems are known for reversibly forming visible images in this way. In one such system, a liquid electrochromic material is used as an imaging medium, and a set of first electrodes co-operate with one or more counterelectrodes to cause deposition of colored material onto selected ones of the first electrodes which have electrical potentials applied to them, to form an image. Typically the first electrodes are transparent conductive members. Erasure is achieved either by the removal of the potentials and the passage of time, or by reversal of the potentials. One kind of electrode configuration which has been suggested for the first electrodes of such systems is the so-called 7-bar configuration, in which seven straight bars are arranged to form the general shape of a square-sided figure-8. By energizing selected ones of the bars, each of the numerals from 0 to 9 may be depicted.
In the concurrently filed patent application in the joint names of M. S. Dye and M. J. Redman entitled "Method and Apparatus for Forming Visible Images" U.S. Ser. No. 784,493 filed on Apr. 4, 1977, there is described and claimed a method and apparatus for forming a visible image comprising selectively applying electrical potentials across an electrochoromic material. The potentials are applied by co-operating electrode means, and the electrochromic material and at least one of the electrode means are moved relative to one another. This latter electrode means comprises a plurality of electrode elements that are individually electrically energizable.